Post updated 2019-07-24. Ed. Fault Consideration & Fault Exclusion ISO 13849-1, Clause 7 [1, 7] discusses the need for fault consideration and fault exclusion. Fault consideration is examining the components and sub-systems used in the safety-related part of the control system (SRP/CS) and making a list of all possible faults. This is a non-trivial exercise!
Read MoreInterlocking Devices: The Good, The Bad and the Ugly
Note: A shorter version of this article was published in the May 2012 edition of Manufacturing Automation Magazine. When designing safeguarding systems for machines, one of the basic building blocks is the movable guard. Movable guards can be doors, panels, gates or other physical barriers that can be opened without using tools. Each of these…
Read MoreInterlock Architectures — Part 6: Comparing North American and International Systems
Note: This article references now-obsolete versions of standards. Please use the current editions in your work! — DN 2022-08-18 I’ve now written six posts on circuit architectures for the safety-related parts of control systems, including this one. In this post, I will compare the International and North American systems. Comparing the requirements is not intended…
Read MoreCSA Z1002 Risk Assessment Standard – 60 Day Public Review
Get more information on CSA Z1002. The draft of this document is now available for public review through CSA.
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